When the Surface Pro 3 launched, Microsoft made a bold claim: This is the tablet that can replace your laptop.

Really?

We set out to test Microsoft’s assertion for not just the Surface Pro 3, but for all tablets. We looked at more than 700 tablets and 2,000 laptops, digging into the specs that make a difference, like RAM and storage, display size, battery, and connectivity.

Of course, for power users such as software developers, pro video editors, and serious gamers, there's still only one no-compromise mobile device: the laptop. Until tablets get more responsive keyboards and support fully featured applications, the physical specs don’t matter.

But that's not to say tablets aren't catching up. Let’s take a look at the data.

RAM: Laptops start with much, much more

Even casual users might notice a lack of RAM. The less RAM a device has, the more often it will need to dump old information from its memory. You’ll see this when you return to an old browsing tab or jump from a game to email and back. Less RAM means these apps will need to refresh more often—a minor nuisance that can become particularly irritating to the avid multi-tasker.

Here’s a look at the RAM included in 50 recent laptops. Note that today’s laptops tend to start with 4- to 8GB of RAM, enough to store information from several applications at once.

The Surface Pro 3’s 4GB of RAM is actually a solid amount for a tablet, but nothing special next to what most laptops provide.(Note that flash memory can help out when RAM runs out, but it is slower.)

RAM winner: Laptops

Storage: Laptops easily prevail

A device’s internal storage determines how much stuff you can cram into it, from photos to music to high-definition videos.

Currently, most tablets come standard with between 16- and 64GB of space. A few come in variations with 128-, 256-, or 512GB, but you’ll have to pay a handsome sum for those. For example, a 512GB Surface Pro 3 will run you nearly $2,000.

Here’s a plot of entry-level tablets’ storage vs. price. Note how the vast majority are clumped below 50GB, and that MSRP is strongly correlated with the storage amount.

A tablet apologist might argue that everything is moving to the cloud anyway—who needs over 64GB of storage when you can buy five times that space for a reasonable monthly fee?

The reality is that most consumers simply aren’t that disciplined. People still want a device where they can dump their 30,000 photos or entire digital music collection without thinking—a fundamental problem for the tablet.

Storage winner: Laptops

Display: You'd think laptops would be better

So far, the specs haven’t been kind to the tablet, which has failed to match the laptop in all three categories. In fairness, however, we’ve been playing on the laptop’s home turf. Performance, RAM, and storage have never been strengths for mobile devices, so let’s turn to one of the tablet’s big assets: the display.

Here’s a look at the pixel density on some of today’s most popular tablets. Since 2013, the average tablet’s display has boasted 218 pixels per inch—pretty crisp for devices that tend to measure from 7 to 11 inches, diagonally.

Comparing that 218 pixels per inch on a tablet to 116 pixels per inch on a laptop isn’t completely fair: Laptops have larger screens on average, and thus need less density to achieve a sharp display. But even after factoring in typical screen sizes (about nine inches for a tablet, 13 for a laptop), the tablet still wins handily. Unless you buy a pricey MacBook Pro with Retina Display, tablets simply sport better screens than their laptop rivals.

Display winner: Tablets

Battery Life: Tablets lead by a wide margin

Battery life is a bit harder to assess. For comparing two phones, using battery capacity (milliampere-hours, or mAh) is a pretty good bet, given that each device is of roughly the same size and shape. But once you get into tablets and laptops, the form factors start varying significantly. A 15-inch laptop needs far more battery capacity than a 7-inch tablet just to make it through the afternoon.

So in the end, the best comparison point we have is vendor-reported battery life. It’s not perfect, because manufacturers's measuring methods and fudge factors can vary. Nevertheless, it's a number the vendors are willing to stand by.

Here’s a chart with battery life for 50 of the most popular modern laptops.

It’s worth noting that 10 hours is by far the most common vendor-reported battery life for tablets. This could be because tablet-makers have learned they must hit 10 hours to be taken seriously. More cynically, it could be a particularly egregious example of number-fudging. Either way, the gap is big enough to hand tablets the victory.

Battery life winner: Tablets

Connectivity: Tablets have little room to spare

It’s the last thing you think about when you’re buying the device, and often the first problem that comes up at home: ports and connectivity.

Tablets have come a long way since the original iPad, which featured nothing more than a 30-pin charge port. But they still lag far behind laptops in connectivity.

Virtually every laptop on the market (in 2013 and 2014) has a USB port, we found, compared to only 27 percent of modern tablets. The discrepancy is similar for HDMI ports, at 82 percent (laptops) versus 15 percent (tablets).

A typical projector or printer will almost always work with your laptop, and will rarely ever work with your tablet. Today, that’s still a problem.

Yes, tech companies have built various workarounds for tablets, like Apple TV for the iPad or Chromecast for the Nexus, but neither has the same universal reliability of plugging an HP LaserJet into your Lenovo ThinkPad. There’s just no consistency in the world of tablets, so individual vendors have had to form separate, proprietary solutions.

The closest thing to a standard on tablets is the micro-USB, which you can find on 57% of devices. That’s progress, but that’s nothing like good ol' USB.

Connectivity winner: Laptops

Laptops win, but tablets are learning

The laptop remains safe—for now. In three out of five productivity specs, the tablet failed to compete.

But the tablet is making progress, riding its battery-life advantage and banking on new technologies (like cloud storage, Chromecast, and Airplay) to overcome its remaining deficiencies. We’ll have to wait and see whether Microsoft’s claim was ultimately wrong…or just a little early.

Behind the Spec Sheet seeks to draw new insights based on hardware data. Produced by FindtheBest, a company that aggregates specs and features in a centralized database, this weekly guest column will share data-driven discoveries and surprises, and attempt to expose common misconceptions.

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